Climate change climate modes and climate impacts largescale

Climate change, climate modes, and climate impacts

“…. large-scale seasonal indices…are remarkably good predictiors of ecological variation…” (Hallet et al 2004)

Modal variability Ecological correlations with modes and IAV are known from: • Terrestrial • Marine • Physiological • Ecosystem • Community • Population

Climate and Ecosystems The challenge facing ecologists is to identify the appropriate climatic variables to use (Hallet et al 2004) Moist Dry Frozen

Ecosystems respond to syndromes of climate: energy balance, water balance and not single variables Growing season length Note the reversed signs: warm springs mean dry summers

Modes and IAV 1. Periodic 2. Spatially coherent 3. Correlated changes in physics 4. Climate changes may be “projected” into modal patterns and frequencies

Modes and IAV 1. Produce spatially correlated responses 2. Modify multiple governing variables simultaneously 3. Affect populations by spatial correlation, producing longterm effects by e. g. affecting entire age cohorts

Interannual variability carbon fluxes Whoa Bacastow and Keeling

Clues to complex causation Was this ENSO or land use change Most of the Indonesian wildfire burned in landscapes like those to the right Or is that the wrong question?

Climate affects ecosystems and ecosystem services It always has, but the nature and severity of the responses, the vulnerability, of human-dominated systems is different from that of more natural systems